Technical description
Burner on / Internal power check required (Section A)
What causes this fault?
This is not a mechanical failure but rather a status indicator showing the burner is active and the system is performing a routine internal power check. It confirms that the electrical components are working correctly and the boiler is successfully firing up to provide heat. You may see this light flicker or stay steady briefly while the boiler initiates its startup sequence.
DIY fix possible
No action is typically required as this is a status indicator rather than a fault.If the boiler fails to fire despite the light being on, check that your room thermostat is turned up.Ensure your gas supply is active and credit is on the meter.